In vitro resistance to fracture of roots obturated with Resilon or gutta-percha.

Introduction: There have been varied results from studies comparing postendodontic fracture resistance between teeth obturated with Resilon or gutta-percha. This study was performed to evaluate the fracture resistance of roots obturated by using Resilon (RealSeal system) or gutta-percha (with AH Plus sealer).

Methods: Eighty extracted human mandibular single-rooted premolars stored in 10% formalin were used in the study. They were prepared by using a crown-down technique, debrided with NaOCl, ethylenediaminetetraacetic acid, and sterile water and divided into 4 groups. Obturation was performed by using the lateral condensation method. The negative control group consisted of unfilled specimens, and the positive control group consisted of those obturated with flowable, dual-cure composite resin. All root specimens were stored for 2 weeks in 100% humidity to allow complete setting of the sealer. Each specimen was mounted in acrylic in a polyvinyl ring and tested for fracture resistance with the Universal testing machine. The loading fixture of the machine was mounted with its spherical tip aligned with the center of the canal opening of each root. A vertical loading force was applied until it fractured the root. The force values were subjected to statistical analysis including analysis of variance and Fisher least significant difference testing.

Results: Teeth obturated with Resilon were more resistant to fracture than those obturated with gutta-percha. The difference was found to be highly significant (P=.00001).

Conclusions: Resilon increased the resistance to fracture of single-rooted teeth in vitro.